quick question

if an amp is rated at 75w x 4 RMS,

how many watts would that produce at 2 channels 2 Ohms?

300W x 2 RMS @ 2 Ohm??

I would think more like 200-250W RMS.

Well it would have to be 1ohm stereo stable, but anywhere between 150 and 600 x 2

SR20, still havent sold that e12a or just havent changed your siggy?

my e12a is fixing to go through a transformation. :D

this is one thing I never really understood. How do you calculate wattage when you bridge an amp? Other than just what the box says.

I don't understand why the amp would have to be 1ohm stereo stable.

because each channel of the amp will only be seing a 1 ohm load when the total resistance is 2 ohms.

this is one thing I never really understood. How do you calculate wattage when you bridge an amp? Other than just what the box says.

I don't understand why the amp would have to be 1ohm stereo stable.


Say an amp does 25x2 @ 4ohm and 50x2 @ 2ohm. That amp would have to put out sqrt(25*4)=10Vrms per channel before clipping to pull that off. If it's only 2ohm stereo stable, then the maximum current the amp can support is 10/2=5 amps. When you bridge, the voltage from the L and R channels add together, so your bridged channel is putting out 20Vrms. If it's putting out 20V, and can only support 5 amps, then the minimum impedance it can safely run at when bridged is 20/5=4ohm.

that was really hard to understand, but I get it. I never would have figured that out myself. Thanks.